Introduction 3.Models of Domestic Automobiles and Tractors (1)Automobile model:including three parts:the head,middle and the tail. Head Middle Tail Catalog numbers of special cars and enterprise custom codes.The front part is letters,and the rear part can be letters or numbers. Product serial number,expressed by a number,and usually is the serial number of improvements The code of vehicles'principal characters,expressed by two numbers The vehicles'category codes,expressed by a number Code of company name,expressed by two to three letters Figure 0-1 Meanings of numbers and letters in automobile models 机被与电子工程学原 Automobile and Tractor Northwest A&F UniversityAutomobile and Tractor Northwest A&F University Introduction 3. Models of Domestic Automobiles and Tractors (1) Automobile model: including three parts: the head, middle and the tail. Catalog numbers of special cars and enterprise custom codes. The front part is letters, and the rear part can be letters or numbers. Product serial number, expressed by a number, and usually is the serial number of improvements The code of vehicles’ principal characters, expressed by two numbers The vehicles’ category codes, expressed by a number Code of company name, expressed by two to three letters Head Middle Tail Figure 0-1 Meanings of numbers and letters in automobile models